Are there any projects where you can detect and measure the width of a crack? I am using tensorflow and labeling the data sets for now.
Depending on the nature of your images, the usual method for doing this sort of thing would be to use an edge detection filter on your image and look for pairs of parallel lines. Such lines might imply the presence of a crack. A Hough transform on the filtered image would then provide the position and orientation of the crack. A convolutional neural network could certainly learn to detect edges (and hence cracks), which might be all that you need.